fs/nfs/nfs4filelayout.c

   1 /*
   2  *  Module for the pnfs nfs4 file layout driver.
   3  *  Defines all I/O and Policy interface operations, plus code
   4  *  to register itself with the pNFS client.
   5  *
   6  *  Copyright (c) 2002
   7  *  The Regents of the University of Michigan
   8  *  All Rights Reserved
   9  *
  10  *  Dean Hildebrand <dhildebz@umich.edu>
  11  *
  12  *  Permission is granted to use, copy, create derivative works, and
  13  *  redistribute this software and such derivative works for any purpose,
  14  *  so long as the name of the University of Michigan is not used in
  15  *  any advertising or publicity pertaining to the use or distribution
  16  *  of this software without specific, written prior authorization. If
  17  *  the above copyright notice or any other identification of the
  18  *  University of Michigan is included in any copy of any portion of
  19  *  this software, then the disclaimer below must also be included.
  20  *
  21  *  This software is provided as is, without representation or warranty
  22  *  of any kind either express or implied, including without limitation
  23  *  the implied warranties of merchantability, fitness for a particular
  24  *  purpose, or noninfringement.  The Regents of the University of
  25  *  Michigan shall not be liable for any damages, including special,
  26  *  indirect, incidental, or consequential damages, with respect to any
  27  *  claim arising out of or in connection with the use of the software,
  28  *  even if it has been or is hereafter advised of the possibility of
  29  *  such damages.
  30  */
  31
  32 #include <linux/nfs_fs.h>
  33 #include <linux/nfs_page.h>
  34 #include <linux/module.h>
  35
  36 #include "internal.h"
  37 #include "nfs4filelayout.h"
  38
  39 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  40
  41 MODULE_LICENSE("GPL");
  42 MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
  43 MODULE_DESCRIPTION("The NFSv4 file layout driver");
  44
  45 #define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
  46
  47 static loff_t
  48 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  49                             loff_t offset)
  50 {
  51         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  52         u64 stripe_no;
  53         u32 rem;
  54
  55         offset -= flseg->pattern_offset;
  56         stripe_no = div_u64(offset, stripe_width);
  57         div_u64_rem(offset, flseg->stripe_unit, &rem);
  58
  59         return stripe_no * flseg->stripe_unit + rem;
  60 }
  61
  62 /* This function is used by the layout driver to calculate the
  63  * offset of the file on the dserver based on whether the
  64  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  65  */
  66 static loff_t
  67 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  68 {
  69         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  70
  71         switch (flseg->stripe_type) {
  72         case STRIPE_SPARSE:
  73                 return offset;
  74
  75         case STRIPE_DENSE:
  76                 return filelayout_get_dense_offset(flseg, offset);
  77         }
  78
  79         BUG();
  80 }
  81
  82 static int filelayout_async_handle_error(struct rpc_task *task,
  83                                          struct nfs4_state *state,
  84                                          struct nfs_client *clp,
  85                                          int *reset)
  86 {
  87         if (task->tk_status >= 0)
  88                 return 0;
  89
  90         *reset = 0;
  91
  92         switch (task->tk_status) {
  93         case -NFS4ERR_BADSESSION:
  94         case -NFS4ERR_BADSLOT:
  95         case -NFS4ERR_BAD_HIGH_SLOT:
  96         case -NFS4ERR_DEADSESSION:
  97         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
  98         case -NFS4ERR_SEQ_FALSE_RETRY:
  99         case -NFS4ERR_SEQ_MISORDERED:
 100                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 101                         "flags 0x%x\n", __func__, task->tk_status,
 102                         clp->cl_exchange_flags);
 103                 nfs4_schedule_session_recovery(clp->cl_session);
 104                 break;
 105         case -NFS4ERR_DELAY:
 106         case -NFS4ERR_GRACE:
 107         case -EKEYEXPIRED:
 108                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 109                 break;
 110         case -NFS4ERR_RETRY_UNCACHED_REP:
 111                 break;
 112         default:
 113                 dprintk("%s DS error. Retry through MDS %d\n", __func__,
 114                         task->tk_status);
 115                 *reset = 1;
 116                 break;
 117         }
 118         task->tk_status = 0;
 119         return -EAGAIN;
 120 }
 121
 122 /* NFS_PROTO call done callback routines */
 123
 124 static int filelayout_read_done_cb(struct rpc_task *task,
 125                                 struct nfs_read_data *data)
 126 {
 127         int reset = 0;
 128
 129         dprintk("%s DS read\n", __func__);
 130
 131         if (filelayout_async_handle_error(task, data->args.context->state,
 132                                           data->ds_clp, &reset) == -EAGAIN) {
 133                 dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
 134                         __func__, data->ds_clp, data->ds_clp->cl_session);
 135                 if (reset) {
 136                         pnfs_set_lo_fail(data->lseg);
 137                         nfs4_reset_read(task, data);
 138                 }
 139                 rpc_restart_call_prepare(task);
 140                 return -EAGAIN;
 141         }
 142
 143         return 0;
 144 }
 145
 146 /*
 147  * We reference the rpc_cred of the first WRITE that triggers the need for
 148  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 149  * rfc5661 is not clear about which credential should be used.
 150  */
 151 static void
 152 filelayout_set_layoutcommit(struct nfs_write_data *wdata)
 153 {
 154         if (FILELAYOUT_LSEG(wdata->lseg)->commit_through_mds ||
 155             wdata->res.verf->committed == NFS_FILE_SYNC)
 156                 return;
 157
 158         pnfs_set_layoutcommit(wdata);
 159         dprintk("%s ionde %lu pls_end_pos %lu\n", __func__, wdata->inode->i_ino,
 160                 (unsigned long) NFS_I(wdata->inode)->layout->plh_lwb);
 161 }
 162
 163 /*
 164  * Call ops for the async read/write cases
 165  * In the case of dense layouts, the offset needs to be reset to its
 166  * original value.
 167  */
 168 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 169 {
 170         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 171
 172         rdata->read_done_cb = filelayout_read_done_cb;
 173
 174         if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
 175                                 &rdata->args.seq_args, &rdata->res.seq_res,
 176                                 task))
 177                 return;
 178
 179         rpc_call_start(task);
 180 }
 181
 182 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 183 {
 184         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 185
 186         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 187
 188         /* Note this may cause RPC to be resent */
 189         rdata->mds_ops->rpc_call_done(task, data);
 190 }
 191
 192 static void filelayout_read_release(void *data)
 193 {
 194         struct nfs_read_data *rdata = (struct nfs_read_data *)data;
 195
 196         rdata->mds_ops->rpc_release(data);
 197 }
 198
 199 static int filelayout_write_done_cb(struct rpc_task *task,
 200                                 struct nfs_write_data *data)
 201 {
 202         int reset = 0;
 203
 204         if (filelayout_async_handle_error(task, data->args.context->state,
 205                                           data->ds_clp, &reset) == -EAGAIN) {
 206                 dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
 207                         __func__, data->ds_clp, data->ds_clp->cl_session);
 208                 if (reset) {
 209                         pnfs_set_lo_fail(data->lseg);
 210                         nfs4_reset_write(task, data);
 211                 }
 212                 rpc_restart_call_prepare(task);
 213                 return -EAGAIN;
 214         }
 215
 216         filelayout_set_layoutcommit(data);
 217         return 0;
 218 }
 219
 220 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
 221 static void prepare_to_resend_writes(struct nfs_write_data *data)
 222 {
 223         struct nfs_page *first = nfs_list_entry(data->pages.next);
 224
 225         data->task.tk_status = 0;
 226         memcpy(data->verf.verifier, first->wb_verf.verifier,
 227                sizeof(first->wb_verf.verifier));
 228         data->verf.verifier[0]++; /* ensure verifier mismatch */
 229 }
 230
 231 static int filelayout_commit_done_cb(struct rpc_task *task,
 232                                      struct nfs_write_data *data)
 233 {
 234         int reset = 0;
 235
 236         if (filelayout_async_handle_error(task, data->args.context->state,
 237                                           data->ds_clp, &reset) == -EAGAIN) {
 238                 dprintk("%s calling restart ds_clp %p ds_clp->cl_session %p\n",
 239                         __func__, data->ds_clp, data->ds_clp->cl_session);
 240                 if (reset) {
 241                         prepare_to_resend_writes(data);
 242                         pnfs_set_lo_fail(data->lseg);
 243                 } else
 244                         rpc_restart_call_prepare(task);
 245                 return -EAGAIN;
 246         }
 247
 248         return 0;
 249 }
 250
 251 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 252 {
 253         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 254
 255         if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
 256                                 &wdata->args.seq_args, &wdata->res.seq_res,
 257                                 task))
 258                 return;
 259
 260         rpc_call_start(task);
 261 }
 262
 263 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 264 {
 265         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 266
 267         /* Note this may cause RPC to be resent */
 268         wdata->mds_ops->rpc_call_done(task, data);
 269 }
 270
 271 static void filelayout_write_release(void *data)
 272 {
 273         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 274
 275         wdata->mds_ops->rpc_release(data);
 276 }
 277
 278 static void filelayout_commit_release(void *data)
 279 {
 280         struct nfs_write_data *wdata = (struct nfs_write_data *)data;
 281
 282         nfs_commit_release_pages(wdata);
 283         if (atomic_dec_and_test(&NFS_I(wdata->inode)->commits_outstanding))
 284                 nfs_commit_clear_lock(NFS_I(wdata->inode));
 285         nfs_commitdata_release(wdata);
 286 }
 287
 288 struct rpc_call_ops filelayout_read_call_ops = {
 289         .rpc_call_prepare = filelayout_read_prepare,
 290         .rpc_call_done = filelayout_read_call_done,
 291         .rpc_release = filelayout_read_release,
 292 };
 293
 294 struct rpc_call_ops filelayout_write_call_ops = {
 295         .rpc_call_prepare = filelayout_write_prepare,
 296         .rpc_call_done = filelayout_write_call_done,
 297         .rpc_release = filelayout_write_release,
 298 };
 299
 300 struct rpc_call_ops filelayout_commit_call_ops = {
 301         .rpc_call_prepare = filelayout_write_prepare,
 302         .rpc_call_done = filelayout_write_call_done,
 303         .rpc_release = filelayout_commit_release,
 304 };
 305
 306 static enum pnfs_try_status
 307 filelayout_read_pagelist(struct nfs_read_data *data)
 308 {
 309         struct pnfs_layout_segment *lseg = data->lseg;
 310         struct nfs4_pnfs_ds *ds;
 311         loff_t offset = data->args.offset;
 312         u32 j, idx;
 313         struct nfs_fh *fh;
 314         int status;
 315
 316         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 317                 __func__, data->inode->i_ino,
 318                 data->args.pgbase, (size_t)data->args.count, offset);
 319
 320         if (test_bit(NFS_DEVICEID_INVALID, &FILELAYOUT_DEVID_NODE(lseg)->flags))
 321                 return PNFS_NOT_ATTEMPTED;
 322
 323         /* Retrieve the correct rpc_client for the byte range */
 324         j = nfs4_fl_calc_j_index(lseg, offset);
 325         idx = nfs4_fl_calc_ds_index(lseg, j);
 326         ds = nfs4_fl_prepare_ds(lseg, idx);
 327         if (!ds) {
 328                 /* Either layout fh index faulty, or ds connect failed */
 329                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
 330                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
 331                 return PNFS_NOT_ATTEMPTED;
 332         }
 333         dprintk("%s USE DS: %s\n", __func__, ds->ds_remotestr);
 334
 335         /* No multipath support. Use first DS */
 336         data->ds_clp = ds->ds_clp;
 337         fh = nfs4_fl_select_ds_fh(lseg, j);
 338         if (fh)
 339                 data->args.fh = fh;
 340
 341         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 342         data->mds_offset = offset;
 343
 344         /* Perform an asynchronous read to ds */
 345         status = nfs_initiate_read(data, ds->ds_clp->cl_rpcclient,
 346                                    &filelayout_read_call_ops);
 347         BUG_ON(status != 0);
 348         return PNFS_ATTEMPTED;
 349 }
 350
 351 /* Perform async writes. */
 352 static enum pnfs_try_status
 353 filelayout_write_pagelist(struct nfs_write_data *data, int sync)
 354 {
 355         struct pnfs_layout_segment *lseg = data->lseg;
 356         struct nfs4_pnfs_ds *ds;
 357         loff_t offset = data->args.offset;
 358         u32 j, idx;
 359         struct nfs_fh *fh;
 360         int status;
 361
 362         if (test_bit(NFS_DEVICEID_INVALID, &FILELAYOUT_DEVID_NODE(lseg)->flags))
 363                 return PNFS_NOT_ATTEMPTED;
 364
 365         /* Retrieve the correct rpc_client for the byte range */
 366         j = nfs4_fl_calc_j_index(lseg, offset);
 367         idx = nfs4_fl_calc_ds_index(lseg, j);
 368         ds = nfs4_fl_prepare_ds(lseg, idx);
 369         if (!ds) {
 370                 printk(KERN_ERR "NFS: %s: prepare_ds failed, use MDS\n",
 371                         __func__);
 372                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
 373                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
 374                 return PNFS_NOT_ATTEMPTED;
 375         }
 376         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s\n", __func__,
 377                 data->inode->i_ino, sync, (size_t) data->args.count, offset,
 378                 ds->ds_remotestr);
 379
 380         data->write_done_cb = filelayout_write_done_cb;
 381         data->ds_clp = ds->ds_clp;
 382         fh = nfs4_fl_select_ds_fh(lseg, j);
 383         if (fh)
 384                 data->args.fh = fh;
 385         /*
 386          * Get the file offset on the dserver. Set the write offset to
 387          * this offset and save the original offset.
 388          */
 389         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 390
 391         /* Perform an asynchronous write */
 392         status = nfs_initiate_write(data, ds->ds_clp->cl_rpcclient,
 393                                     &filelayout_write_call_ops, sync);
 394         BUG_ON(status != 0);
 395         return PNFS_ATTEMPTED;
 396 }
 397
 398 /*
 399  * filelayout_check_layout()
 400  *
 401  * Make sure layout segment parameters are sane WRT the device.
 402  * At this point no generic layer initialization of the lseg has occurred,
 403  * and nothing has been added to the layout_hdr cache.
 404  *
 405  */
 406 static int
 407 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 408                         struct nfs4_filelayout_segment *fl,
 409                         struct nfs4_layoutget_res *lgr,
 410                         struct nfs4_deviceid *id,
 411                         gfp_t gfp_flags)
 412 {
 413         struct nfs4_deviceid_node *d;
 414         struct nfs4_file_layout_dsaddr *dsaddr;
 415         int status = -EINVAL;
 416         struct nfs_server *nfss = NFS_SERVER(lo->plh_inode);
 417
 418         dprintk("--> %s\n", __func__);
 419
 420         /* FIXME: remove this check when layout segment support is added */
 421         if (lgr->range.offset != 0 ||
 422             lgr->range.length != NFS4_MAX_UINT64) {
 423                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 424                         __func__);
 425                 goto out;
 426         }
 427
 428         if (fl->pattern_offset > lgr->range.offset) {
 429                 dprintk("%s pattern_offset %lld too large\n",
 430                                 __func__, fl->pattern_offset);
 431                 goto out;
 432         }
 433
 434         if (!fl->stripe_unit || fl->stripe_unit % PAGE_SIZE) {
 435                 dprintk("%s Invalid stripe unit (%u)\n",
 436                         __func__, fl->stripe_unit);
 437                 goto out;
 438         }
 439
 440         /* find and reference the deviceid */
 441         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->pnfs_curr_ld,
 442                                    NFS_SERVER(lo->plh_inode)->nfs_client, id);
 443         if (d == NULL) {
 444                 dsaddr = get_device_info(lo->plh_inode, id, gfp_flags);
 445                 if (dsaddr == NULL)
 446                         goto out;
 447         } else
 448                 dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 449         /* Found deviceid is being reaped */
 450         if (test_bit(NFS_DEVICEID_INVALID, &dsaddr->id_node.flags))
 451                         goto out_put;
 452
 453         fl->dsaddr = dsaddr;
 454
 455         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 456                 dprintk("%s Bad first_stripe_index %u\n",
 457                                 __func__, fl->first_stripe_index);
 458                 goto out_put;
 459         }
 460
 461         if ((fl->stripe_type == STRIPE_SPARSE &&
 462             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 463             (fl->stripe_type == STRIPE_DENSE &&
 464             fl->num_fh != dsaddr->stripe_count)) {
 465                 dprintk("%s num_fh %u not valid for given packing\n",
 466                         __func__, fl->num_fh);
 467                 goto out_put;
 468         }
 469
 470         if (fl->stripe_unit % nfss->rsize || fl->stripe_unit % nfss->wsize) {
 471                 dprintk("%s Stripe unit (%u) not aligned with rsize %u "
 472                         "wsize %u\n", __func__, fl->stripe_unit, nfss->rsize,
 473                         nfss->wsize);
 474         }
 475
 476         status = 0;
 477 out:
 478         dprintk("--> %s returns %d\n", __func__, status);
 479         return status;
 480 out_put:
 481         nfs4_fl_put_deviceid(dsaddr);
 482         goto out;
 483 }
 484
 485 static void filelayout_free_fh_array(struct nfs4_filelayout_segment *fl)
 486 {
 487         int i;
 488
 489         for (i = 0; i < fl->num_fh; i++) {
 490                 if (!fl->fh_array[i])
 491                         break;
 492                 kfree(fl->fh_array[i]);
 493         }
 494         kfree(fl->fh_array);
 495         fl->fh_array = NULL;
 496 }
 497
 498 static void
 499 _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 500 {
 501         filelayout_free_fh_array(fl);
 502         kfree(fl);
 503 }
 504
 505 static int
 506 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 507                          struct nfs4_filelayout_segment *fl,
 508                          struct nfs4_layoutget_res *lgr,
 509                          struct nfs4_deviceid *id,
 510                          gfp_t gfp_flags)
 511 {
 512         struct xdr_stream stream;
 513         struct xdr_buf buf;
 514         struct page *scratch;
 515         __be32 *p;
 516         uint32_t nfl_util;
 517         int i;
 518
 519         dprintk("%s: set_layout_map Begin\n", __func__);
 520
 521         scratch = alloc_page(gfp_flags);
 522         if (!scratch)
 523                 return -ENOMEM;
 524
 525         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 526         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 527
 528         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 529          * num_fh (4) */
 530         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 531         if (unlikely(!p))
 532                 goto out_err;
 533
 534         memcpy(id, p, sizeof(*id));
 535         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 536         nfs4_print_deviceid(id);
 537
 538         nfl_util = be32_to_cpup(p++);
 539         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 540                 fl->commit_through_mds = 1;
 541         if (nfl_util & NFL4_UFLG_DENSE)
 542                 fl->stripe_type = STRIPE_DENSE;
 543         else
 544                 fl->stripe_type = STRIPE_SPARSE;
 545         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 546
 547         fl->first_stripe_index = be32_to_cpup(p++);
 548         p = xdr_decode_hyper(p, &fl->pattern_offset);
 549         fl->num_fh = be32_to_cpup(p++);
 550
 551         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 552                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 553                 fl->pattern_offset);
 554
 555         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 556          * Futher checking is done in filelayout_check_layout */
 557         if (fl->num_fh >
 558             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 559                 goto out_err;
 560
 561         if (fl->num_fh > 0) {
 562                 fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
 563                                        gfp_flags);
 564                 if (!fl->fh_array)
 565                         goto out_err;
 566         }
 567
 568         for (i = 0; i < fl->num_fh; i++) {
 569                 /* Do we want to use a mempool here? */
 570                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 571                 if (!fl->fh_array[i])
 572                         goto out_err_free;
 573
 574                 p = xdr_inline_decode(&stream, 4);
 575                 if (unlikely(!p))
 576                         goto out_err_free;
 577                 fl->fh_array[i]->size = be32_to_cpup(p++);
 578                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 579                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 580                                i, fl->fh_array[i]->size);
 581                         goto out_err_free;
 582                 }
 583
 584                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 585                 if (unlikely(!p))
 586                         goto out_err_free;
 587                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 588                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 589                         fl->fh_array[i]->size);
 590         }
 591
 592         __free_page(scratch);
 593         return 0;
 594
 595 out_err_free:
 596         filelayout_free_fh_array(fl);
 597 out_err:
 598         __free_page(scratch);
 599         return -EIO;
 600 }
 601
 602 static void
 603 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 604 {
 605         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 606
 607         dprintk("--> %s\n", __func__);
 608         nfs4_fl_put_deviceid(fl->dsaddr);
 609         kfree(fl->commit_buckets);
 610         _filelayout_free_lseg(fl);
 611 }
 612
 613 static struct pnfs_layout_segment *
 614 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 615                       struct nfs4_layoutget_res *lgr,
 616                       gfp_t gfp_flags)
 617 {
 618         struct nfs4_filelayout_segment *fl;
 619         int rc;
 620         struct nfs4_deviceid id;
 621
 622         dprintk("--> %s\n", __func__);
 623         fl = kzalloc(sizeof(*fl), gfp_flags);
 624         if (!fl)
 625                 return NULL;
 626
 627         rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
 628         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
 629                 _filelayout_free_lseg(fl);
 630                 return NULL;
 631         }
 632
 633         /* This assumes there is only one IOMODE_RW lseg.  What
 634          * we really want to do is have a layout_hdr level
 635          * dictionary of <multipath_list4, fh> keys, each
 636          * associated with a struct list_head, populated by calls
 637          * to filelayout_write_pagelist().
 638          * */
 639         if ((!fl->commit_through_mds) && (lgr->range.iomode == IOMODE_RW)) {
 640                 int i;
 641                 int size = (fl->stripe_type == STRIPE_SPARSE) ?
 642                         fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 643
 644                 fl->commit_buckets = kcalloc(size, sizeof(struct list_head), gfp_flags);
 645                 if (!fl->commit_buckets) {
 646                         filelayout_free_lseg(&fl->generic_hdr);
 647                         return NULL;
 648                 }
 649                 fl->number_of_buckets = size;
 650                 for (i = 0; i < size; i++)
 651                         INIT_LIST_HEAD(&fl->commit_buckets[i]);
 652         }
 653         return &fl->generic_hdr;
 654 }
 655
 656 /*
 657  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 658  *
 659  * return true  : coalesce page
 660  * return false : don't coalesce page
 661  */
 662 static bool
 663 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 664                    struct nfs_page *req)
 665 {
 666         u64 p_stripe, r_stripe;
 667         u32 stripe_unit;
 668
 669         if (!pnfs_generic_pg_test(pgio, prev, req) ||
 670             !nfs_generic_pg_test(pgio, prev, req))
 671                 return false;
 672
 673         p_stripe = (u64)prev->wb_index << PAGE_CACHE_SHIFT;
 674         r_stripe = (u64)req->wb_index << PAGE_CACHE_SHIFT;
 675         stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 676
 677         do_div(p_stripe, stripe_unit);
 678         do_div(r_stripe, stripe_unit);
 679
 680         return (p_stripe == r_stripe);
 681 }
 682
 683 void
 684 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 685                         struct nfs_page *req)
 686 {
 687         BUG_ON(pgio->pg_lseg != NULL);
 688
 689         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 690                                            req->wb_context,
 691                                            0,
 692                                            NFS4_MAX_UINT64,
 693                                            IOMODE_READ,
 694                                            GFP_KERNEL);
 695         /* If no lseg, fall back to read through mds */
 696         if (pgio->pg_lseg == NULL)
 697                 nfs_pageio_reset_read_mds(pgio);
 698 }
 699
 700 void
 701 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 702                          struct nfs_page *req)
 703 {
 704         BUG_ON(pgio->pg_lseg != NULL);
 705
 706         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 707                                            req->wb_context,
 708                                            0,
 709                                            NFS4_MAX_UINT64,
 710                                            IOMODE_RW,
 711                                            GFP_NOFS);
 712         /* If no lseg, fall back to write through mds */
 713         if (pgio->pg_lseg == NULL)
 714                 nfs_pageio_reset_write_mds(pgio);
 715 }
 716
 717 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
 718         .pg_init = filelayout_pg_init_read,
 719         .pg_test = filelayout_pg_test,
 720         .pg_doio = pnfs_generic_pg_readpages,
 721 };
 722
 723 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
 724         .pg_init = filelayout_pg_init_write,
 725         .pg_test = filelayout_pg_test,
 726         .pg_doio = pnfs_generic_pg_writepages,
 727 };
 728
 729 static bool filelayout_mark_pnfs_commit(struct pnfs_layout_segment *lseg)
 730 {
 731         return !FILELAYOUT_LSEG(lseg)->commit_through_mds;
 732 }
 733
 734 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
 735 {
 736         if (fl->stripe_type == STRIPE_SPARSE)
 737                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
 738         else
 739                 return j;
 740 }
 741
 742 struct list_head *filelayout_choose_commit_list(struct nfs_page *req)
 743 {
 744         struct pnfs_layout_segment *lseg = req->wb_commit_lseg;
 745         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 746         u32 i, j;
 747         struct list_head *list;
 748
 749         /* Note that we are calling nfs4_fl_calc_j_index on each page
 750          * that ends up being committed to a data server.  An attractive
 751          * alternative is to add a field to nfs_write_data and nfs_page
 752          * to store the value calculated in filelayout_write_pagelist
 753          * and just use that here.
 754          */
 755         j = nfs4_fl_calc_j_index(lseg,
 756                                  (loff_t)req->wb_index << PAGE_CACHE_SHIFT);
 757         i = select_bucket_index(fl, j);
 758         list = &fl->commit_buckets[i];
 759         if (list_empty(list)) {
 760                 /* Non-empty buckets hold a reference on the lseg */
 761                 get_lseg(lseg);
 762         }
 763         return list;
 764 }
 765
 766 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 767 {
 768         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 769
 770         if (flseg->stripe_type == STRIPE_SPARSE)
 771                 return i;
 772         else
 773                 return nfs4_fl_calc_ds_index(lseg, i);
 774 }
 775
 776 static struct nfs_fh *
 777 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 778 {
 779         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 780
 781         if (flseg->stripe_type == STRIPE_SPARSE) {
 782                 if (flseg->num_fh == 1)
 783                         i = 0;
 784                 else if (flseg->num_fh == 0)
 785                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 786                         return NULL;
 787         }
 788         return flseg->fh_array[i];
 789 }
 790
 791 static int filelayout_initiate_commit(struct nfs_write_data *data, int how)
 792 {
 793         struct pnfs_layout_segment *lseg = data->lseg;
 794         struct nfs4_pnfs_ds *ds;
 795         u32 idx;
 796         struct nfs_fh *fh;
 797
 798         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
 799         ds = nfs4_fl_prepare_ds(lseg, idx);
 800         if (!ds) {
 801                 printk(KERN_ERR "NFS: %s: prepare_ds failed, use MDS\n",
 802                         __func__);
 803                 set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
 804                 set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
 805                 prepare_to_resend_writes(data);
 806                 data->mds_ops->rpc_release(data);
 807                 return -EAGAIN;
 808         }
 809         dprintk("%s ino %lu, how %d\n", __func__, data->inode->i_ino, how);
 810         data->write_done_cb = filelayout_commit_done_cb;
 811         data->ds_clp = ds->ds_clp;
 812         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
 813         if (fh)
 814                 data->args.fh = fh;
 815         return nfs_initiate_commit(data, ds->ds_clp->cl_rpcclient,
 816                                    &filelayout_commit_call_ops, how);
 817 }
 818
 819 /*
 820  * This is only useful while we are using whole file layouts.
 821  */
 822 static struct pnfs_layout_segment *find_only_write_lseg(struct inode *inode)
 823 {
 824         struct pnfs_layout_segment *lseg, *rv = NULL;
 825
 826         spin_lock(&inode->i_lock);
 827         list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list)
 828                 if (lseg->pls_range.iomode == IOMODE_RW)
 829                         rv = get_lseg(lseg);
 830         spin_unlock(&inode->i_lock);
 831         return rv;
 832 }
 833
 834 static int alloc_ds_commits(struct inode *inode, struct list_head *list)
 835 {
 836         struct pnfs_layout_segment *lseg;
 837         struct nfs4_filelayout_segment *fl;
 838         struct nfs_write_data *data;
 839         int i, j;
 840
 841         /* Won't need this when non-whole file layout segments are supported
 842          * instead we will use a pnfs_layout_hdr structure */
 843         lseg = find_only_write_lseg(inode);
 844         if (!lseg)
 845                 return 0;
 846         fl = FILELAYOUT_LSEG(lseg);
 847         for (i = 0; i < fl->number_of_buckets; i++) {
 848                 if (list_empty(&fl->commit_buckets[i]))
 849                         continue;
 850                 data = nfs_commitdata_alloc();
 851                 if (!data)
 852                         goto out_bad;
 853                 data->ds_commit_index = i;
 854                 data->lseg = lseg;
 855                 list_add(&data->pages, list);
 856         }
 857         put_lseg(lseg);
 858         return 0;
 859
 860 out_bad:
 861         for (j = i; j < fl->number_of_buckets; j++) {
 862                 if (list_empty(&fl->commit_buckets[i]))
 863                         continue;
 864                 nfs_retry_commit(&fl->commit_buckets[i], lseg);
 865                 put_lseg(lseg);  /* associated with emptying bucket */
 866         }
 867         put_lseg(lseg);
 868         /* Caller will clean up entries put on list */
 869         return -ENOMEM;
 870 }
 871
 872 /* This follows nfs_commit_list pretty closely */
 873 static int
 874 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
 875                            int how)
 876 {
 877         struct nfs_write_data   *data, *tmp;
 878         LIST_HEAD(list);
 879
 880         if (!list_empty(mds_pages)) {
 881                 data = nfs_commitdata_alloc();
 882                 if (!data)
 883                         goto out_bad;
 884                 data->lseg = NULL;
 885                 list_add(&data->pages, &list);
 886         }
 887
 888         if (alloc_ds_commits(inode, &list))
 889                 goto out_bad;
 890
 891         list_for_each_entry_safe(data, tmp, &list, pages) {
 892                 list_del_init(&data->pages);
 893                 atomic_inc(&NFS_I(inode)->commits_outstanding);
 894                 if (!data->lseg) {
 895                         nfs_init_commit(data, mds_pages, NULL);
 896                         nfs_initiate_commit(data, NFS_CLIENT(inode),
 897                                             data->mds_ops, how);
 898                 } else {
 899                         nfs_init_commit(data, &FILELAYOUT_LSEG(data->lseg)->commit_buckets[data->ds_commit_index], data->lseg);
 900                         filelayout_initiate_commit(data, how);
 901                 }
 902         }
 903         return 0;
 904  out_bad:
 905         list_for_each_entry_safe(data, tmp, &list, pages) {
 906                 nfs_retry_commit(&data->pages, data->lseg);
 907                 list_del_init(&data->pages);
 908                 nfs_commit_free(data);
 909         }
 910         nfs_retry_commit(mds_pages, NULL);
 911         nfs_commit_clear_lock(NFS_I(inode));
 912         return -ENOMEM;
 913 }
 914
 915 static void
 916 filelayout_free_deveiceid_node(struct nfs4_deviceid_node *d)
 917 {
 918         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
 919 }
 920
 921 static struct pnfs_layoutdriver_type filelayout_type = {
 922         .id                     = LAYOUT_NFSV4_1_FILES,
 923         .name                   = "LAYOUT_NFSV4_1_FILES",
 924         .owner                  = THIS_MODULE,
 925         .alloc_lseg             = filelayout_alloc_lseg,
 926         .free_lseg              = filelayout_free_lseg,
 927         .pg_read_ops            = &filelayout_pg_read_ops,
 928         .pg_write_ops           = &filelayout_pg_write_ops,
 929         .mark_pnfs_commit       = filelayout_mark_pnfs_commit,
 930         .choose_commit_list     = filelayout_choose_commit_list,
 931         .commit_pagelist        = filelayout_commit_pagelist,
 932         .read_pagelist          = filelayout_read_pagelist,
 933         .write_pagelist         = filelayout_write_pagelist,
 934         .free_deviceid_node     = filelayout_free_deveiceid_node,
 935 };
 936
 937 static int __init nfs4filelayout_init(void)
 938 {
 939         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
 940                __func__);
 941         return pnfs_register_layoutdriver(&filelayout_type);
 942 }
 943
 944 static void __exit nfs4filelayout_exit(void)
 945 {
 946         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
 947                __func__);
 948         pnfs_unregister_layoutdriver(&filelayout_type);
 949 }
 950
 951 MODULE_ALIAS("nfs-layouttype4-1");
 952
 953 module_init(nfs4filelayout_init);
 954 module_exit(nfs4filelayout_exit);